Rubber impeller



Oct. 8, 1940. cs. G. MORSE 2,217,231

RUBBER IMPELLER Filed April 4, 1938 VII/I I r W GEORGE 6-170? IN\ 'ENTOR.

J A TTQRNEY.

Patented Oct. 8, 1940 UNITED STATES PATENT OFFICE George G. Morse, Denver, 0010., assignor to Morse Bros. Machinery Company, Denver, 0010., a corporation of Colorado Application April 4, 1938, Serial No. 199,909

6 Claims.

This invention relates to improvements in rubber impellers of the type disclosed in my Patent No. 2,115,997 dated May 3, 1938, for I.m-;-

pellers and lining construction, of which the present application is a division.

It is now well-known that rubber and compounds thereof withstand abrasive influences better than most metal or other materials. Heretofore, rubber impeller construction has required 10 inner reinforcement of some kind as shown in the above-mentioned copending application, which discloses the use of metal and/or fabric to strengthen rubber impeller structure.

According to the present invention, an im- 5 peller for use in liquid agitation and/or aeration, especially in froth flotation operations, may be made entirely of rubber, or compounds thereof, with no added mechanical reinforcement, since rubber and its compounds when produced according to the present invention will have suficient strength and durability to satisfy the structural requirementsof such use.

An object of this invention is to provide such an impeller that is made entirely of rubber, or

, compounds of rubber, having a yielding wearresistant surface and a relatively more rigid inner structure formed integrally therewith, thus providing a light weight and long-wearing impeller, that is well suited for use in mineral pulp or the like.

A further object is the provision of an im peller of this character that requires no added mechanical reinforcement, thus saving in the time, labor and expense of producing it, as well as simplifying assembly for use.

Other objects and advantages reside in details of design and construction that will be more fully disclosed in, the following description and in the drawing wherein;

40 Figure 1 is a sectional view of an impeller made according to the present invention; and

Figure 2 is a bottom plan view of the same.

In the drawing, reference character 5 denotes a rotary shaft, preferably hollow as at 6, on

which is a disk-like impeller I having a shaftengaging hub 8, and vanes 9. The hub, disk and vanes are preferably made of vulcanized rubber compounds and are shown integral, which is the preferred form. The outer surfaces la of the impeller element, are made of yielding,

wear-resisting rubber while the inner structure is composed of a compound of rubber that vulcanizes into a relative stiffer mass. Both comcome an integral unit.

The advantage of forming the component parts integrally is that when the yieldable wear surface is penetrated due to excessive wear there is no peeling of this cover layer from the inner section as would occur otherwise.

Thearrangement of the vanes on the lower side of the impeller disk is a copy, in the present instance, of the arrangement disclosed in the United States patent to A. J. Weinig, No. 1,998,694, issued April 23, 1935. In such an ar- 10 rangement certain of the vanes are arranged substantially radial while others are arranged along chords of the circular disk I. In use, the radial vanes impart a centrifugal component of force to sur ounding liquid tending to throw it! it outwardly, d at the same time sucking air, or any other aeration agent, down through the hollow shaft to be mixed, intimately, with the liquid. The vanes that are positioned near the periphery of the disk along chords thereof, slice 20 through the liquid and tend to draw it inwardly of the impeller. Thus intense agitation and thorough aeration are imparted to the liquid that. is acted upon by the impeller, and the impeller must be rigid enough to withstand distor- 25 tion.

When such liquid contains suspended solids, as in a mineral pulp in a flotation operation, the abrasive influence is present to a great degree, as the impeller rotates rapidly therein. The 30 rubber withstands the impact with the suspended solids, in an excellent manner, and, being light in weight, a minimum amount of power is required to drive the improved impeller, and wear on bearings and other associated machine parts 35 is greatly reduced.

The soft outer surfaces of the impeller resist wear and abrasion, while the inner structure gives strength, form and a degree of rigidity to the impeller while at the same time being sufli- 40 ciently yieldable to permit the outer surface to exert a substantial degree of elasticity in withstanding the bombardment of abrasive particles in the material under treatment. The difference in elasticity is effected by different compounding of the inner rubber and the surface rubber, prior to vulcanizing. The process of vulcanizing unites theentire mass into an inseparable unit possessing the desired properties. 5

The present construction also permits use of a corrosion-resistant cover-layer on the impeller and whenever impellers are to be operated in materials of a corrosive nature the cover-layer' may be compounded to render it especially resistant 55 v I to such corrosive action without impairing its elasticity to anyappreciable degree.

It will be understood that the impeller design illustrated is merely typical of what may be used as it is within contemplation of the invention that the construction herein described may be applied to various types of impeller design as required in use.

Where the expressions rubber or rubbe compound" are used in the specification, they are intended to cover so-called rubber substitutes" spirit and scope of the hereunto appended claims.

What I claim and desire to secure by Letters Patent is:

1. As a new article of manufacture, an impeller element having means for its attachment to a rotary shaft and comprising a disk portion and integral vanes projectingfrom a face of the disk, the impeller being composed entirely of rubber with the inner portion thereof of a composition stiffened sufilciently to withstand the stresses of normal operation without distortion, the outer wear surfaces on the stifl'ened portion being relatively more yielding.

2. As a new article of manufacture, an impeller element having means for its attachment to a. ro-

. tary shaft and comprising a disk portion and integral vanesprojecting from a face of the disk, the impeller being composed entirely of rubber stiffened to a degree suflicient to withstand the integral vanes projecting from a face of the disk, the impeller being composed entirely of rubber with the inner portion thereof of a composition stiffened sufficiently to withstand the stresses of normal operation without distortion, the outer wear surfaces on the stiffened portion being relatively more yielding, andthe inner and outer compositions being vulcanized into an integral mass.

4. As a new article of manufacture, an impeller element having a hollow hub for its attachment 'to a rotary shaft and comprising a disk portion and integral vanes projecting from a face of the disk, the impeller being composed entirely of rubber with the inner portion thereof of a composition stiffened sufficiently to withstand the stresses of normal operation without distortion, the outer wear surfaces on the stiffened portion being relatively more yielding.

5. As a new article of manufacture, an impeller element having means for its attachment to a rotary shaft and comprising a disk portion and integral vanes projecting from a face of the disk, the impeller being composed entirely of rubber with the inner portion thereof of a composition stiffened sufliciently to withstand the stresses of normal operation without distortion, the outer wear surfaces on the stiffened portion being relatively more yielding and of corrosion-resistant. composition, and the innerand outer compositions being vulcanized into an integral mass.

6. As a new article of manufacture, animpeller element having means for its attachment to a rotaryshaft and comprising a disk portion and integral vanes projecting from a face of the disk, the impeller being composed entirely of rubber with the inner portion thereof of a composition stiffened sufliciently to withstand the stresses of normal operation without distortion, the outer wear surfaces on the stiffened portion being of a relatively high degree of elasticity.

' GEORGE G. MORSE. 

